Same chapter1 markDifficulty: Easy
An alpha particle is:
Radioactivity
2 marksDifficulty: Easy
Define the half-life of a radioactive substance.
Original Khojo Papers practice question — not from a past board paper.
Answer
The half-life is the time taken for half the nuclei in a given sample of the substance to decay. It is a constant for a given nuclide and does not depend on the size of the sample or on the physical or chemical conditions.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
After n half-lives the fraction remaining is (1/2)n.
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